A connecting element for connecting two workpieces without cutting is already known. The connecting element comprises a shank having a multiplicity of parallel annular projections, which form grooves between them and which lie in a plane extending perpendicularly to the longitudinal axis of the connecting element. The connecting element is driven through the components by means of pressure and rotation, giving rise to a connection by friction welding (DE 10 2011 014 870 A1).
A connecting element for connecting two workpieces, which has a multiplicity of encircling annular projections with a constant, spacing on a shank is furthermore known, said annular projections extending obliquely to the longitudinal axis and parallel to one another DE 10 2011 109 815 A1). This connecting element is driven in with the application of pressure and rotation in order to produce a firm connection by means of frictional heating and local deformation of the component materials.